Differential cytokine expression and regulation of human anti-pig xenogeneic responses by modified porcine dendritic cells.
BACKGROUND
Porcine dendritic cells (DC) are likely to be pivotal cells in the initiation of stimulatory and potential tolerogenic responses to xenoantigens, however, there are limited studies characterizing these antigen presenting cells.


METHODS
Porcine PBMC (CD172a(+)) were cultured with GM-CSF and IL-4 and phenotype and functional capabilities assessed. Lipopolysaccharide (LPS), IL-10, and IL-3 were added to the GM-CSF/IL-4 DC cultures to determine phenotypic and functional changes. Quantitative real-time polymerase chain reaction (PCR) for key cytokines was performed and the modified porcine DC were further assessed by primary mixed lymphocyte reaction to determine the effect of LPS, IL-10, and IL-3 on stimulatory capability.


RESULTS
Porcine PBMC (CD172(+)) cultured with GM-CSF and IL-4 produced cells with DC morphology, which were major histocompatability complex (MHC) class II(+), CD14(-/lo), and CD1a(lo). Addition of IL-10 or IL-3 to GM-CSF/IL-4 DC cultures produced cells with lower levels of MHC class II and higher levels of antigen uptake consistent with less mature DC. Quantitative real-time PCR of DC showed the addition of IL-10 induced an increase in IL-10 mRNA, no detectable IL-12, and reduced IL-6 mRNA. The addition of IL-3 to DC cultures decreased IL-12, IL-6 and tumor necrosis factor (TNF), with no change in IL-10 mRNA. GM-CSF/IL-4 DC induced strong human lymphocyte proliferation, compared with significantly reduced stimulatory capacity induced by IL-10 and IL-3 treated DC cultures.


CONCLUSIONS
The profound effect on differential DC cytokine profile and reduced human anti-pig responses has important therapeutic implications in xenotransplantation. The mechanism of altered regulation warrants further investigation.
Layton
Daniel Stuart
DS
CSIRO, Australian Animal Health Laboratories, Geelong, Victoria, Australia.
Bean
Andrew Gerard
AG
Dodge
Natalie Michelle
NM
Strom
A David G
AD
Sandrin
Mauro Sergio
MS
Ierino
Francesco Libero
FL
D000818:Animals; D016207:Cytokines / Q000235:genetics*; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology*; D015870:Gene Expression / Q000187:drug effects; D006084:Graft Rejection / Q000276:immunology / Q000517:prevention & control; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D006801:Humans; D007108:Immune Tolerance; D066298:In Vitro Techniques; D016753:Interleukin-10 / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins; D013552:Swine; D013556:Swine, Miniature; D013601:T-Lymphocytes / Q000276:immunology; D014183:Transplantation, Heterologous / Q000276:immunology*
D016207:Cytokines; D007377:Interleukin-3; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D011994:Recombinant Proteins; D016753:Interleukin-10; D015847:Interleukin-4; D016178:Granulocyte-Macrophage Colony-Stimulating Factor